pendleton



, 2 Sheets-Sheet l.

J. M. PENDLETON.

Patented June 8, 1886.

jaw/72W Nv PETERS, Phma-Liihognpher. Walhinglnm D. C.

(No Model.)

SYSTEM FOR CONTROLLING SECONDARY BATTERY CIRCUITS. No. 343,392.

a ww

(No Model.) 2 Sheets-Sheet 2.

J. M. PENDLETON.

SYSTEM FOR CONTROLLING SECONDARY BATTERY GIRGUITS. No. 343,392. PatentedJune 8, 1886.

jizw/ziar N. PETERS. Phm-Lahn wn Wishinglon. n. c.

UNITED' STATES PATENT I OFFICE.

JOHN M. PENDLETON, OF NEV YORK, N. Y., ASSIGNOR TO THE EQUITABLEELECTRIC COMPANY, OF SAME PLACE.

SYSTEM FOR CONTROLLING SECONDARY-BATTERY CIRCUITS.

SPECIFICATION forming part of Letters Patent No. 343,392, dated June 8,1886.

Serial No. 186,286. (No model.)

To all whom it may concern-.-

Be it known that 1, JOHN M. PENDLETON, a citizen of the United States,residing at New York, county and State of New York, have invented acertain new and Improved System for Controlling Secondary-BatteryCircuits, of which the following is a specification.

It is a wellknown fact that hydrogen gencrates heat when caused toimpinge on a metal. In this circuit-controlling system for secondarybatteries I take advantage of this fact by allowing the heat sogenerated to actuate a thermostat, which is constructed and arranged toclose an electric circuit in communication with the charging-station,and thereby break the charging-circuit supplying current to thesecondary batteries, or to give notice to the attendant when an excessof current is supplied or the batteries are fully 0 charged. Thehydrogen used for this purpose is that which is evolved at one of thesuboxide plates of the battery.

In the simple application of the principle involved in this inventionthe tl'lermostat act- 1- 5 uated by the heat generated by the hydrogenescaping from the electrode is caused to close a circuit which may besupplied with current from the battery itself, and in this circuit isincluded an alarm or indicator located near the charging dynamoclectricmachine, so that the attendant can, upon notice, direct a part or thewhole of the current from the batterycircuit; but in most cases I preferto make the apparatus automatic in its action; and to this end I includein the circuit operated by the thermostat the coil of an electro-magnet,the armature of which, when attracted by the current flowing through thethermostatic circuit, is caused to break the charging-circuit of thedynamo-electric machine. Now, as

the thermostat, by cooling,will,react on its circuit'closer when thesupply of current is cut oil, which will take place as soon as thecharging-current stops, the armaturewould, by its retractile spring, bedrawn away from the magnet and again close the charging-circuit; but asthis rcclosing of the charging-circuit should not occur until thesecondary battery has discharged to about the limit of its practicalworking clcctro-motivc force, I provide a simple means for holding thearmature down, which consists of a fine-wire coil surrounding the coreof the magnet and connected to the terminals of one of the cells orparts of the secondary batteries. The re- M sistance of said coil andcircuit is such that only suliicient current flows through it to holdthe armature down when the elcctro-motive force of the battery isbetween its working limits, the amount of current required for thispurpose being a very small percentage of the capacity of the cell orpart of the battery. As soon as the electro-motive force of the bat teryapproaches its minimum working limit, the current flowing through thishigh-1c sistance coil is insufiicient to cause the magnet to hold thearmature,which, moving away from the magnet, again closes thechargingcircuit.

In the accompanying drawings, Figure 1, 7c Sheet 1, represents myimproved circuit-con troller applied to the charging-circuit of asecondary battery. Fig. 2, Sheet 1., is an enlarged view of thethermostatic cut-out; and Fig. 3, Sheet 2, represents the application of7 my thermostatic cut-out to a number of batteries charged from acentral station.

The improved thermostatic cut-out devised by me is clearly shown in Fig.2. It consists of a mass of spongy platinum held in the openend tube, a,which, by the tube b, is brought into communication with apart of theintcrior of the battery 0, where hydrogen is gencrated by providing thelower end of the tube '1) with an inverted cup placed over the upper endof one of the plates, which is a suboxide or negative plate, when thecharging current is flowing through the battery from the binding-post ato the binding-post 0". Attached to the tube a, and surrounding it inthe form of a coil, is the thermostat composed of two strips ofdifferent metals, (1 and 0, so selected that the coefficient ofexpansion of the inside strip, (I, shall be greater than that of theouter strip, 0. The coil (1 6 will consequently tend IOO f to break thecircuit; at f.

f, connected by a wire to the terminal 0 of the battery, and the lever gsimilarly constructed and arranged, so that its light end bears againstthe stop 9', clear of the lever f. The end e of the thermostat islocated below the heavy end of the lever 9, but away from it when theapparatus is in normal condition.

e e are stops for limiting the play of the free end of the thermostat.

The thermostatic operated circuit comprises the wire h from thelever gand the wire h from the terminal 0 of the battery, and in this circuitis shown the callor indicator i,W .i0h may be at any convenient place atany distant locality, to give notice to the attendant of thedynamo-electric machine that the battery is being overcharged or isfully charged. The operation of this part of the invention is asfollows: When the heat generated in the tube a afl'ects the thermostaticcoil d e, the end e moves and strikes the heavy end of the lever g,lifting it and causing its light end to come in contact with the leverf, thereby closing the circuit from c to 0 through the line h, call orindicator 73, line I, lever f, and stop f,- but this closing of thecircuit is only momentary, allowing enough current to flow to actuatethe instrument-t, for as the end e of the thermostat continues to move,the lever 9 causes the lever This prevents an unnecessary waste ofcurrent, as the thermostat, if arranged to act directly on thecircuitcont-act, would, by reason of its slowness of action, keep thecircuit closed a considerable length of time and cause an unnecessarywaste of stored energy. It will also be observed that the thermostat isnot included in the circuit, and is therefore unafi'ected by the heat ofthe current.

I will now, by referring to Fig. 1, describe the appliances employed byme in automatically operating charging-circuits of secondary batteries.The thermostatic cut-out a b d e f g is applied to the cell c of thebattery. The working-circuit j passes from the terminal 0 of this cellto the opposite terminal, 0 of the last cell of the battery, and thedynamo-electric machine It is also connected to these terminals by thelines k 10 respectively. In the line k" is included the armature landcontact-stop m of the electro-magnetic cut-out, on the cores 1:. ofwhich are placed the coils o and p. The coil 0, which is ofcomparatively coarse wire, is included in the circuit h hof thethermostatic cut-out, and the coil 10, which is of fine wire of highresistance, is placed in circuit with one. of the cells or part of thebattery-as the last cellby the line g, which joins one end of it todash-pots t.

New, assuming the parts to be in-the position shown in. the drawingsthedynamo-electric machine charging the battery-as soon as hydrogen isevolved from the cell c, as before described, the thermostat operatesand closes the circuit h h at f and g, and the current from this cell,flowing through the coil 0, causes the magnet n to attract its armatureZ, thereby breaking the circuit of the dynamoelectric machine at thestop an. The secondary battery now alone supplies current to theworking-line j, sufficient current flowing through the high-resistancecoil 11 to cause the magnet to hold its armature 1 against the action ofits retractile spring Z,- but when the electro-inotive force of thebattery falls to about its minimum normal working limit, sulficientcurrent does not flow through the coil p to cause the magnet to overcomethe resilience of the spring Z, and consequently the armature is therebywithdrawn from the magnet and again closes the dynamo-electricmachinecircuit at m.

When several batteries are connected in multiple are and charged from adynamoelectric machine at a central station, thermostatic cut-outs madeaccording to my invention may be applied to them, as shown at Fig. 3, sothat when either of the batteries becomes fully charged it is cut out ofthe circuit and notice automatically sent to the charging or centralstation, giving the number of the battery or station so cut out. Thebatteries and automatic controlling apparatus and the arrangement of thecircuits are, with the exception of a slight addition to thecircuitcloser similar to the apparatus and circuits shown in Fig. 1, andcorresponding parts at the three substations shown, are marked withletters similar to those of Fig. 1. It is therefore unnecessary to againdescribe the construction and operation of thesame. The princip'aladdition made is a commutator formed on the end of the armature 1,against which bears a contact-spring, 8, connected by line 8 to earth.The commutators T have different numbers of metallic projectionsat eachof the orrfrom the magnet 12., No. 2 two points of contact, and so on.

To cause a perceptible interval of time to ;occur between the makes andbreaks of the commutators r with their springs s, the armatures Z areconnected to the moving pistons of The charging-lines k of the batteriesall join the main k from the charging- ;machine It at the centralstation, and one of the mains, as k is connected at the central stationto earth by the line u, in which is included the indicator or callapparatus a. An I flowing through said closed circuit retains theammeter or other current-indicator, '0, maybe inserted in one of themains to indicate the amount of current flowing through the mains andthe condition, resistance, or number of multiple circuits takingcurrent.

By referring to the previous description of my automatic controller theoperation of the controllers here shown will be readily understood. Thecondition of the instrument at station No. 3 shows that thecharging-current has been out off by, the armature Z, which has beenmoved away from the stop m; but in so moving, the spring 8 has mademetallic contact with the armature Z three times,each tooth closing theearth-circuit through the part of the line if from armature Z to oneterminal of the battery, from the other terminal of the battery by lineIt to main 7.. through the machine It, and through the indicator or callapparatus a by the line a to earth, thereby actuating the call apparatusthree times, which notifies the attendant that station No. 3 is out Off,so that he can adjust the current to meet the requirements of the linesnow in circuit. Now, when the circuit at Z m of station No. 3 is againclosed, three electrical impulses flow over the earthcircuit and actuatethe call apparatus a, notifying the attendant that said station is againdrawing current from the main, so that he may again adjust the current,and also as certain the time during which the sub-stations are receivingcurrent from the main, by keeping a record of the signals indicated bythe call apparatus a. The opening and closing signals being somewhatdifferent, may be readily distinguished from each other.

Having now described my invention, what I claim, and desire to secure byLetters Patent, 1S

1. In an apparatus for controlling secondarybattery circuits, thecombination, with the battery and its charging-circuit, of aheat-generator excited by gas escaping from the battery, a thermostatactuated by the heat-generator, and a circuit-breaker or cut-out in thecharging-circuit actuated by a current allowed to flow by thethermostat.

2. In an apparatus for controlling secondarybattery circuits, thecombination, with the battery and its charging-circuit, of aheat-generator excited by gas escaping from the battery, a thermostatactuated by the heat-generator, a circuit-breaker or cut-out in thecharging-circuit actuated to open the charging-circuit by a currentallowed to flow by the thermostat when the battery is charged, and aclosed circuit from a part of the battery so connected to be cut outthat the current cut-out in open position until the electromotive forceof the battery reaches its lower working limit.

3. In an apparatus for controlling secondarybattery circuits, incombination, a secondary battery, a heat-generator composed of spongyplatinum, a gas-tube located over a suboxide plate of the battery, athermostat surrounding the heat-generator, a circuit-closer actuated bythe thermostat and included in circuit with a coil on an electro-magnet,a dynamo-electric machine connected to the battery, and circuitcloserincluded in its circuit and actuated by the armature of theelectro-magnet, substantially as set forth.

4. In an apparatus for controlling secondarybattery circuits, incombination, a secondary battery,a thermostatic cut-out actuated by heatgenerated by hydrogen given off from the ele ments of the battery, anelectroanagnet, a coil surrounding the same included in circuit with thethermostatic cut-out, a coil of high resistance, also surrounding theelectro-magnet and included in a closed circuit with part of thesecondary battery, and a cut-out in the chargingcircuit actuated by thearmature of the electro-magnet, substantially as set forth.

5. In an apparatus for controlling secondarybattery cireuits,incombination,the secondary battery 0, heat-generatora b, thermostat d ec, lever g, leverf, stop f, upon which the end of the lever f rests,said stop being connected to one terminal of the battery, and theindicating-circuit 7b 71, connected by part it to lever g, and by partIt to the other terminal of battery, substantially as set forth.

6. In an apparatus for controlling the charging-circuits oftwo or moresecondary batteries, in combination with each of the batteries, anelectro-magnet energized by currents from the battery when the batteryisbeing overcharged or is fully charged, a cut-out in the charging mainactuated by the armature of the electromagnet, a normally-open line, anindicating circuit-closer therein actuated by the armature of theelectro-magnet, and a call apparatus or indication-receivcr at thecentral station by which distinctive signals are transmitted from thebatteries to the central station when their respective charging circuitsare opened or closed, substantially as set forth.

In witness whereof I have hereunto set my hand at New York, county andState of New York, this 19th day of December, 1885.

JOHN M. PENDLETON.

\Vitnesses:

ALFRED SHEDLOOlC, H. D. XVILLIAuS.

IIO

